Add 'Latch' state to automation chapter

include/automation-states.html

@@ -1,9 +1,12 @@
 
 <p>
   In order to understand how automation in Ardour works, it is necessary to
-  understand the four states of automation. They are: <kbd
-  class=menu>Manual</kbd>, <kbd class=menu>Play</kbd>, <kbd
-  class=menu>Write</kbd>, and <kbd class=menu>Touch</kbd>.
+  understand the five states of automation. They are: 
+  <kbd class=menu>Manual</kbd>,
+  <kbd class=menu>Play</kbd>,
+  <kbd class=menu>Write</kbd>,
+  <kbd class=menu>Touch</kbd>,
+  and <kbd class=menu>Latch</kbd>.
 </p>
 
 <figure class=right>
@@ -36,13 +39,23 @@
   control during playback; all such settings are written to the lane the
   control is in. This defines the lane's automation curve in the interval being
   played, and overwrites any existing automation curve in the lane being
-  manipulated.
+  manipulated. As this might be sometimes dangerous, this state is automatically
+  changed to <kbd class=menu>Touch</kbd> state when playing is stopped.
 </p>
 
 <p>
   <kbd class=menu>Touch</kbd> state is similar to <kbd class=menu>Write</kbd>
-  mode, except it only overwrites sections of a lane's automation curve when
+  state, except it only overwrites sections of a lane's automation curve when
   the control is changed in some way. This allows for changing only the parts
   of an automation curve that are desired to be changed, while leaving the rest
   unchanged.
 </p>
+
+<p>
+  <kbd class=menu>Latch</kbd> state is similar to <kbd class=menu>Touch</kbd>
+  state as it will also change automation when the control is changed in some way
+  during session play back.
+  But additionally it will overwrite the automation curve with the last
+  value that it was changed to until play-back is stopped
+  playing.
+</p>

include/automation.html

@@ -7,10 +7,10 @@
 </p>
 
 <ul>
-  <li>Volume</li>
-  <li>Panning</li>
+  <li>Fader (Volume)</li>
   <li>Trim</li>
   <li>Muting</li>
+  <li>Panning</li>
   <li>Any attached processor's parameters</li>
 </ul>
 
@@ -20,3 +20,11 @@
   played back.
 </p>
 
+<p>
+  To activate automation for a track, click the <kbd class=menu>A</kbd> icon on the track head and check the
+  type of automation you need.
+</p>  
+<figure class=left>
+  <img src="/images/automation-menu1.png">
+  <figcaption class=center>The automation menu.</figcaption>
+</figure>